2 The technology



Memokath 051 Ureter stent is a biocompatible, thermo-expandable, nickel-titanium alloy ureteric stent. It is intended as an alternative to conventional ureteric stents for people with benign or malignant ureteric obstruction. The nickel-titanium alloy has a shape memory effect, which is designed to allow the stent to be more easily inserted and anchored into position. A spiral coil design aims to prevent endothelial ingrowth of the tumour or stricture into the stent so that it can be easily removed. Four different versions of the Memokath 051 stent are available (single or double cone, for either antegrade or retrograde insertion), each in several different lengths. Memokath 051 can be used to treat obstructions elsewhere in the urinary tract, but this is outside the scope of this evaluation.

Care pathway


Ureteric obstruction can be treated by stenting the ureter, creating a nephrostomy or through reconstructive surgery. It must be treated quickly to avoid obstructive renal failure. Nephrostomy or stenting should be done as soon as possible (within 12 hours of diagnosis). For malignant obstruction, the NICE guideline on prostate cancer recommends decompression of the upper urinary tract by nephrostomy or inserting a double‑J stent. The NICE guideline on bladder cancer recommends nephrostomy or retrograde stenting (if technically feasible) for people with locally advanced or metastatic bladder cancer. The NICE guideline on acute kidney injury says that all people with upper urinary tract obstruction should be referred to a urologist.

Innovative aspects


Memokath 051 can adapt to the natural curves of the urinary tract because of its tight spiral structure, which also makes it less likely that tissue grows between the coils. According to the company, compared with other stents, it is better tolerated, with fewer stent-related symptoms and complications. It reduces the need for stent replacement and the risk of tissue ingrowth.

Intended use


Memokath 051 is intended for treating ureteric obstruction in adults with benign or malignant strictures. It is contraindicated for children. People with bleeding disorders or using anticoagulant medication are advised to check coagulation parameters, and the stent should not be implanted if their coagulation parameters are not within the range that would be suitable for surgical intervention. For a full list of contraindications and details on using Memokath 051, see the instructions for use.



The cost of Memokath 051 used in the company's submission for the original guidance was £1,690 (excluding VAT). This included the Memokath 051 stent, a guidewire and a dilator-insertion sheath. The company confirmed that there is no change to the cost of Memokath 051 stents.

For more details about the technology, see the website for Memokath 051 Ureter.

  • National Institute for Health and Care Excellence (NICE)